net/mlx4_en: Add XDP_REDIRECT statistics

Add counters for XDP REDIRECT success and failure. This brings the
redirect path in line with metrics gathered via the other XDP paths.

Signed-off-by: Joshua Roys <roysjosh@gmail.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/en_ethtool.c

@@ -197,6 +197,8 @@ static const char main_strings[][ETH_GSTRING_LEN] = {
 
 	/* xdp statistics */
 	"rx_xdp_drop",
+	"rx_xdp_redirect",
+	"rx_xdp_redirect_fail",
 	"rx_xdp_tx",
 	"rx_xdp_tx_full",
 
@@ -428,6 +430,8 @@ static void mlx4_en_get_ethtool_stats(struct net_device *dev,
 		data[index++] = priv->rx_ring[i]->bytes;
 		data[index++] = priv->rx_ring[i]->dropped;
 		data[index++] = priv->rx_ring[i]->xdp_drop;
+		data[index++] = priv->rx_ring[i]->xdp_redirect;
+		data[index++] = priv->rx_ring[i]->xdp_redirect_fail;
 		data[index++] = priv->rx_ring[i]->xdp_tx;
 		data[index++] = priv->rx_ring[i]->xdp_tx_full;
 	}
@@ -519,6 +523,10 @@ static void mlx4_en_get_strings(struct net_device *dev,
 				"rx%d_dropped", i);
 			sprintf(data + (index++) * ETH_GSTRING_LEN,
 				"rx%d_xdp_drop", i);
+			sprintf(data + (index++) * ETH_GSTRING_LEN,
+				"rx%d_xdp_redirect", i);
+			sprintf(data + (index++) * ETH_GSTRING_LEN,
+				"rx%d_xdp_redirect_fail", i);
 			sprintf(data + (index++) * ETH_GSTRING_LEN,
 				"rx%d_xdp_tx", i);
 			sprintf(data + (index++) * ETH_GSTRING_LEN,

drivers/net/ethernet/mellanox/mlx4/en_port.c

@@ -244,6 +244,8 @@ int mlx4_en_DUMP_ETH_STATS(struct mlx4_en_dev *mdev, u8 port, u8 reset)
 	priv->port_stats.rx_chksum_complete = 0;
 	priv->port_stats.rx_alloc_pages = 0;
 	priv->xdp_stats.rx_xdp_drop    = 0;
+	priv->xdp_stats.rx_xdp_redirect = 0;
+	priv->xdp_stats.rx_xdp_redirect_fail = 0;
 	priv->xdp_stats.rx_xdp_tx      = 0;
 	priv->xdp_stats.rx_xdp_tx_full = 0;
 	for (i = 0; i < priv->rx_ring_num; i++) {
@@ -255,6 +257,8 @@ int mlx4_en_DUMP_ETH_STATS(struct mlx4_en_dev *mdev, u8 port, u8 reset)
 		priv->port_stats.rx_chksum_complete += READ_ONCE(ring->csum_complete);
 		priv->port_stats.rx_alloc_pages += READ_ONCE(ring->rx_alloc_pages);
 		priv->xdp_stats.rx_xdp_drop	+= READ_ONCE(ring->xdp_drop);
+		priv->xdp_stats.rx_xdp_redirect += READ_ONCE(ring->xdp_redirect);
+		priv->xdp_stats.rx_xdp_redirect_fail += READ_ONCE(ring->xdp_redirect_fail);
 		priv->xdp_stats.rx_xdp_tx	+= READ_ONCE(ring->xdp_tx);
 		priv->xdp_stats.rx_xdp_tx_full	+= READ_ONCE(ring->xdp_tx_full);
 	}

drivers/net/ethernet/mellanox/mlx4/en_rx.c

@@ -793,11 +793,13 @@ int mlx4_en_process_rx_cq(struct net_device *dev, struct mlx4_en_cq *cq, int bud
 			case XDP_PASS:
 				break;
 			case XDP_REDIRECT:
-				if (xdp_do_redirect(dev, &xdp, xdp_prog) >= 0) {
+				if (likely(!xdp_do_redirect(dev, &xdp, xdp_prog))) {
+					ring->xdp_redirect++;
 					xdp_redir_flush = true;
 					frags[0].page = NULL;
 					goto next;
 				}
+				ring->xdp_redirect_fail++;
 				trace_xdp_exception(dev, xdp_prog, act);
 				goto xdp_drop_no_cnt;
 			case XDP_TX:

drivers/net/ethernet/mellanox/mlx4/mlx4_en.h

@@ -340,6 +340,8 @@ struct mlx4_en_rx_ring {
 	unsigned long csum_complete;
 	unsigned long rx_alloc_pages;
 	unsigned long xdp_drop;
+	unsigned long xdp_redirect;
+	unsigned long xdp_redirect_fail;
 	unsigned long xdp_tx;
 	unsigned long xdp_tx_full;
 	unsigned long dropped;

drivers/net/ethernet/mellanox/mlx4/mlx4_stats.h

@@ -42,9 +42,11 @@ struct mlx4_en_port_stats {
 
 struct mlx4_en_xdp_stats {
 	unsigned long rx_xdp_drop;
+	unsigned long rx_xdp_redirect;
+	unsigned long rx_xdp_redirect_fail;
 	unsigned long rx_xdp_tx;
 	unsigned long rx_xdp_tx_full;
-#define NUM_XDP_STATS		3
+#define NUM_XDP_STATS		5
 };
 
 struct mlx4_en_phy_stats {